A robot wrist of the above-mentioned type is previously known from UK Patent Publication No. GB-A-2 147 877 and is characterized by a great orientation capacity. When using such a robot for water jet cutting, however, it has not been possible to utilize this orientation capacity in full, since the conduits leading to the water jet nozzle in certain positions restrict the freedom of movement of the robot wrist.
From UK Patent Publication No. GB-A-2 120 202 it is known to introduce, from above, a bellows-type conduit in a two-axis, hollow wrist of an industrial robot of a different type. However, this known conduit does not solve the problem mentioned above, since this conduit restricts the rotation of the nozzle around a horizontal axis to about 180.degree..
From the magazine The Industrial Robot, Vol. 12, No. 2, June 1985, pp. 82-85, an industrial robot intended for water jet cutting is previously known. In this robot, the high-pressure water is supplied via a flexible hose wound around the robot arm, which is hardly acceptable from the point of view of personal safety.